Handling data transmission between a wireless network and a mobile station has been a developing concern in third generation (3G) wireless communication systems such as Universal Mobile Telecommunications System (UMTS) and Evolution-Data Optimized or Evolution-Data only (EV-DO).
FIG. 1 illustrates a simplified conventional wireless network 100. The conventional wireless network 100 may include a core network 60, a radio network controller (RNC) 40 connected to the core network 60, and a plurality of mobile base transceiver stations (BTS) 20 also connected to the RNC 40. Together the BTSs 20 and RNC 30 are known as an access network (AN). The BTSs 20 may include RF components for transmitting and receiving signals. The RNC 40 is a component that interfaces with the core network 60, controls the radio transmitters and receivers in the BTSs 20, and may perform other radio access and link maintenance functions. The connection between a BTS 20 to the RNC 30 is known as a “backhaul” link. Mobile stations 10 such as cell phones, wireless laptops, person digital assistant (PDA), and other wireless devices may communicate with a BTS 20 via a radio link or “air interface”. Recently, the capacity of the air interface has exceeded the capacity of the backhaul network, shifting the historical bottleneck from air (wireless) to wire.
Conventionally, the majority of the backhaul links for the BTS 20 are T1 lines with roughly 1.5 Mbps of bandwidth, compared to over 50 Mbps for an ideal air interface between the BTS 20 and the mobile station 10. To deliver advanced services and data such as video and music content, either higher-bandwidth fiber optics or additional T1 lines must be connected to each of the BTSs 20. However, optical fiber is expensive and deployment of additional T1 lines has been slower than anticipated. Also, service assurance policies on T1 lines make them prohibitively expensive. Accordingly, new mobile services are either not offered, or discontinued, if the demands for the services are too great—an ironic situation for service providers trying to sell these new services. Video in particular requires substantial amount of bandwidth, so widespread deployment may not be economically supported because of the backhaul bottleneck.